Comparison of cytologic and acridine-orange flow-cytometric detection of malignant cells in human body cavity fluids

Flow cytometrically (FCM) derived DNA and RNA profiles were studied in acridine orange (AO)-stained body cavity fluid (BCF) specimens obtained from 78 patients with various solid tissue and hematologic malignancies. The ploidy (DNA index), RNA content (RNA index), proliferative activity (% S + G2M) and DNA and RNA scattergram patterns were tested "double-blind" against the cytologic scoring of specimens as malignant, benign or reactive. It was determined that expression of an "abnormal" RNA index (greater than or equal to 2.8) and an elevated proliferative activity (% S + G2M greater than or equal to 7.4) was dependent on the presence of malignancy; 21 of 22 specimens having those abnormal indices had DNA aneuploidy and were cytologically scored as positive. The AO FCM sensitivity and specificity for detecting malignant cells (when measured against cytology scoring) were 61% and 90%, respectively, using the "abnormal" RNA index and % S + G2M cut-offs together with the cellular DNA aneuploidy marker. By supplementing the cytologic scoring with AO FCM DNA and RNA features, the sensitivity for detecting malignant cells was 94%, as compared to 72% for cytology alone. Two specimens gave false-positive FCM results: a tuberculous effusion with a tetraploid subpopulation and a reactive mesothelial proliferation that was diploid and negative cytologically. Scoring for malignancy based on the visual pattern of the DNA and RNA FCM scattergrams, while showing good correlation for aneuploid specimens, in some cases failed to identify diploid disease. The results demonstrate the usefulness of FCM DNA and RNA analysis for supplementing cytologic examination of BCF specimens for the purpose of detecting malignant cells.(ABSTRACT TRUNCATED AT 250 WORDS)     

Usefulness of bile cytology in the diagnostic management of patients with biliary tract obstruction

Eighteen patients with evidence of biliary tract obstruction had a total of 29 satisfactory bile samples submitted for diagnostic cytology during a two-year period. These 29 specimens were reviewed in order to determine if bile cytology is useful in the diagnostic management of patients with obstructive biliary tract disease. Twenty-one of the bile specimens were from patients with malignant biliary stricture, and eight were from patients with benign biliary obstruction. Bile cytology was positive for carcinoma in eight samples from patients with malignant stricture and was inconclusive for malignancy in two. There were no false positives. The diagnostic specificity of bile cytology was 100%, the diagnostic sensitivity was 48%, and the diagnostic accuracy was 62%. When carefully collected and promptly processed, bile proved an excellent specimen for cytologic evaluation and was a valuable adjunct to other diagnostic procedures for the detection of carcinoma causing biliary tract obstruction.     

Flow cytometric analysis and cytopathology of body cavity fluids

A total of 75 samples of body cavity fluids from 71 patients were analyzed by both flow cytometry (FCM), to detect cells with an abnormal DNA content (aneuploidy), and by conventional cytopathology. Samples included 27 pleural fluids, 35 peritoneal fluids, 11 peritoneal washings and 2 pericardial fluids. For cytologic examination, the samples were prepared using standard techniques. Samples for FCM analysis were centrifuged and exposed to a hypotonic solution containing detergent and propidium iodide, a DNA intercalating fluorescent stain. Aneuploidy as well as cytologic malignancy were found in 17 samples. Forty-seven samples had normal DNA histograms by FCM and were also cytologically negative. Four samples suspicious by cytology but normal by FCM were from patients with renal-cell carcinoma (two samples from the same patient), endometrial adenocarcinoma without metastasis and chronic lymphocytic leukemia. Three samples abnormal by FCM but negative by cytology were from patients with ovarian cystadenoma, cirrhosis and uterine leiomyoma. FCM showed aneuploidy in four cytologically negative samples from patients with histologically proven malignancy (lymphoma, colonic adenocarcinoma, cervical squamous cell carcinoma, and endometrial adenosquamous carcinoma). Based on these results, FCM analysis combined with conventional cytopathology yielded 100% sensitivity, 100% predictive value of a negative result and 94% specificity. This rapid and quantitative FCM analysis of body cavity fluids can be a very useful adjunct to conventional diagnostic cytopathology.     

Flow cytometric DNA analysis combined with fine needle aspiration biopsy in the diagnosis of palpable metastases

To determine the diagnostic value of flow cytometric (FCM) DNA analysis in combination with fine needle aspiration (FNA) biopsy, the nuclear DNA content was analyzed in FNA specimens from 155 superficial metastases and 60 benign lymph nodes. The results of FCM DNA analysis were considered to be positive for malignancy if DNA aneuploidy was found or if more than 12% S+G2M cells were present in the aspirate in diploid cases. The diagnostic accuracy of FCM DNA analysis alone in detecting malignancy was 92%, with a sensitivity of 91% and a specificity of 95%. FCM suggested the correct diagnosis in 5 of the 7 cytologically false-negative cases and in 9 of the 12 cytologically indeterminate or suspicious cases.     

DNA flow cytometry of pleural effusions. Comparison with pathology for the diagnosis of malignancy

A study was undertaken to determine the potential value of DNA flow cytometry (FCM) for the diagnosis of malignancy in pleural effusions and to compare its results with those of traditional cytomorphology. Forty-one pleural fluids from 37 patients were evaluated by DNA FCM and routine cytologic techniques. Of the 41 pleural fluids, 29 (70.7%) demonstrated an abnormal DNA content by FCM. Two of the 29 pleural fluids had been originally diagnosed as benign by cytology. Cytologic review of these two cases showed no abnormal cells; therefore, there were no false-negative cases based on cytology. In 12 (29.3%) of the 41 fluids, DNA FCM and cytologic evaluation both indicated benign processes. Our preliminary observations indicate that FCM is an accurate and reliable technique that may be of aid in the diagnosis of malignant effusions. The technique may prove to be of special value in the differential diagnosis of reactive mesothelial cells versus malignant mesothelioma as well as for following patients who receive chemotherapy for malignant pleural effusions. DNA FCM may also complement cytomorphologic diagnoses in other serous, exfoliative or aspiration material.     

Detection of IGF2BP3, HOXB7, and NEK2 mRNA Expression in Brush Cytology Specimens as a New Diagnostic Tool in Patients with Biliary Strictures

Introduction

It is a challenging task to distinguish between benign and malignant lesions in patients with biliary strictures. Here we analyze whether determination of target gene mRNA levels in intraductal brush cytology specimens may be used to improve the diagnosis of bile duct carcinoma.

Materials and Methods

Brush cytology specimens from 119 patients with biliary strictures (malignant: n = 72; benign: n = 47) were analyzed in a retrospective cohort study. mRNA of IGF-II mRNA-binding protein 3 (IGF2BP3), homeobox B7 (HOXB7), Forkhead box M1 (FOXM1), kinesin family member 2C (KIF2C) and serine/threonine kinase NEK2 was determined by semi-quantitative RT-PCR using the ΔCt method.

Results

IGF2BP3 (p<0.0001), HOXB7 (p<0.0001), and NEK2 (p<0.0001) mRNA expression levels were significantly increased in patients with cholangiocarcinoma or pancreatic cancer. Median ΔCt values differed by 3.5 cycles (IGF2BP3), 2.8 cycles (HOXB7) and 1.3 cycles (NEK2) corresponding to 11-fold, 7-fold and 2.5-fold increased mRNA levels in malignant versus benign samples. Sensitivity to detect biliary cancer was 76.4% for IGF2BP3 (80.9% specificity); 72.2% for HOXB7 (78.7% specificity) and 65.3% for NEK2 (72.3% specificity), whereas routine cytology reached only 43.1% sensitivity (85.4% specificity). Diagnostic precision was further improved, when all three molecular markers were assessed in combination (77.8% sensitivity, 87.2% specificity) and achieved 87.5% sensitivity and 87.2% specificity when molecular markers were combined with routine cytology.

Conclusions

Our data suggest that measuring IGF2BP3, HOXB7 and NEK2 mRNA levels by RT-PCR in addition to cytology has the potential to improve detection of malignant biliary disorders from brush cytology specimens.     

Biliary tract brush cytology

OBJECTIVE: To prospectively review brush smears obtained during endoscopic retrograde cholangiopancreatography (ERCP) primarily from the biliary tree. STUDY DESIGN: A total of 175 specimens from 147 patients were included in the study. The smears, prepared directly from the endoscopic brush, were stained by the Papanicolaou technique and analyzed for standard cytologic features. RESULTS: The smears were categorized into benign/reactive, significant atypia and suspicious/positive. The consistent features seen in suspicious or positive smears were tightly cohesive, small, three-dimensional cell clusters that formed cell balls. The cells in the clusters displayed features of malignant cells. CONCLUSION: ERCP-guided brushing is a safe diagnostic procedure for the evaluation of biliary tree lesions. Small, three-dimensional epithelial clusters with marked atypia signify malignancy and warrant the diagnosis of a malignant neoplasm even when only one or two such clusters are seen in the smears. Single cells, cytoplasmic vacuoles and prominent nucleoli are not essential for a diagnosis of malignancy.     

Cytologic and DNA cytometric diagnosis and therapy monitoring of squamous cell carcinoma in situ and malignant melanoma of the cornea and conjunctiva

OBJECTIVE: To investigate the diagnostic accuracy of exfoliative cytology of the cornea and conjunctiva and DNA image cytometry for quality control and monitoring of therapy for malignant neoplasms. STUDY DESIGN: Conjunctival or corneal smears from six cases clinically suspicious for malignant melanomas and eight suspicious for carcinomas in situ were investigated. Smears from 18 cases clinically nonsuspicious for neoplastic diseases served as negative controls. Repeated smears were obtained during and after local mitomycin C (MMC) therapy. RESULTS: In none of 18 nonsuspicious cases, cytology revealed abnormal cells. DNA cytometry showed nonaneuploidy in all of these. All smears from patients with histologically proven malignant melanomas (MM) and squamous cell carcinomas in situ revealed abnormal cells. Image cytometry demonstrated DNA aneuploidy in 66.6% of patients with MM and 80% with carcinoma. Sensitivity of cytology thus was 100% for both MM and carcinoma; specificity also was 100%. DNA measurements after MMC therapy revealed euploid polyploidization of nonneoplastic squamous cells. DNA cytometry provided an objective identification of tumor cell regression. CONCLUSION: Cytologic examination of corneal and conjunctival smears is a noninvasive tool with high diagnostic accuracy for detection of epithelial neoplasms. DNA image cytometry can serve for quality control and for objective monitoring of the effect of local chemotherapy.     

Qualitative and quantitative analysis of peritoneal fluids from women with gynecologic diseases. Comparison of cytology and flow cytometry for the detection of malignancy in lavage and ascitic fluids

A prospective study was undertaken to compare flow cytometric (FCM) analysis to conventional cytologic evaluation for the detection of malignant cells in peritoneal fluids (peritoneal lavages and ascitic fluids) from women with gynecologic diseases. The 94 peritoneal fluids analyzed came from 63 cancer patients (with epithelial ovarian carcinomas) and 31 control patients (with benign gynecologic diseases). The FCM DNA histograms were generated using propidium iodide as a DNA fluorochrome. Samples for cytologic analysis were stained with the standard May-Grünwald-Giemsa or Papanicolaou stains. Of the 94 samples, 90 were evaluable cytologically while 70 were suitable for FCM analysis. The sensitivities were 55% for FCM DNA analysis and 80% for cytologic analysis. FCM DNA analysis had a 30% false-positive rate; cytologic analysis produced no false-positive results. These results indicate that there is no advantage in employing FCM analysis instead of conventional cytologic evaluation for the detection of malignant cells in peritoneal fluids from gynecologic cases.     

Ultrasound-guided fine needle aspiration cytology of impalpable breast lesions in a rural setting. Comparison of cytology with imaging and final outcome

OBJECTIVE: To analyze the effectiveness of fine needle aspiration (FNA) cytology in a multidisciplinary setting in rural Australia and to compare the imaging (mammographic and ultrasound) appearances and cytomorphologic findings with the final outcome. STUDY DESIGN: Prospective analysis of ultrasound-guided FNA cytology results from 426 women, aged 40-86 years, with screening-detected mammographic abnormalities. Cases of microcalcification, assessed mainly by stereotactatic core biopsy, were not included in the study. The FNAs were performed at a rural breast screening and assessment program in New South Wales, Australia, over a three-year period between May 1993 and May 1996. RESULTS: Imaging, FNA and combined imaging and FNA results from 426 women were as follows. The imaging diagnoses included 176 (41%) benign, 34 (8%) probably benign, 17 (4%) equivocal, 104 (24%) suspicious and 95 (23%) malignant cases. The FNA findings showed 59 (14%) no epithelial cells seen (nondiagnostic), 175 (41%) benign, 36 (8%) atypical, 41 (10%) suspicious and 115 (27%) malignant. Combined imaging and cytologic results comprised 224 (52.6%) benign, 10 (2.3%) atypical/equivocal, 59 (13.9%) suspicious and 133 (31.2%) malignant cases. All the malignant cases, by combined assessment, had malignant histology, and all the benign cases behaved in a benign fashion. In 80% of the suspicious lesions, the histologic diagnosis was malignant, but only 10% of the atypical/equivocal lesions had malignant histology. The positive predictive value of diagnosis of malignancy by combined imaging and FNA was 100%, and the false negative rate was 0%. CONCLUSION: Despite the recent surge in the popularity of core biopsy, FNA cytology of impalpable, mammographically detected lesions, when practiced in a multidisciplinary setting, is an extremely accurate test with high sensitivity, specificity, predictive values and efficacy. FNA cytology of the breast is a well-tolerated, relatively noninvasive test with a very low risk of complications. The sensitivity and positive predictive values for malignant and suspicious mammographic categories are also very high.     

Prediction of upper aerodigestive tract cancer by slide-based cytometry.

AIM: To evaluate slide-based cytometry in screening for and following up of carcinoma of the upper aerodigestive tract using swabs for a minimal-invasive approach. METHODS: Laser scanning cytometry (LSC) was used for multiparametric analysis of cells stained for cytokeratin and DNA to determine the DNA-index (DI) of the tumor cells. Histograms with 0.95 < DI < 1.05 and 1.9 < DI < 2.1 were defined as DNA euploid and any other DI as DNA aneuploid. After subsequent HE-staining, single cells were relocalized in order to document morphology. Conventional cytology was also performed on a subset of the slides. Routine histopathology of parallel biopsies served as gold standard in all cases. RESULTS: 115 swabs from 109 patients were obtained from the entire upper aerodigestive tract. 16 swabs were classified as insufficient for LSC. In the remaining 99 specimens, 1 benign lesion was misclassified as malignant, while 61 of the 75 malignant lesions were correctly identified. This corresponds to predictive values of 98.4% and 62.2% for the detection of malignant and benign samples by LSC. CONCLUSION: This pilot study demonstrates the validity of LSC screening for the identification of tumor malignancy in the upper aerodigestive tract from swab collected cytological material.     

Posters. P17 Accuracy of fine needle aspiration cytology in diagnosis of thyroid swellings

Introduction Fine needle aspiration cytology is regarded as the gold standard investigation in diagnosis of thyroid swellings. Published data suggest an overall accuracy rate of 75% 1 in the detection of thyroid malignancy. The aim of this study was to determine the accuracy of FNA cytology in detection of thyroid malignancy in our surgical unit. Methods Between 1989–2002, 144 patients who underwent thyroid resection by single consultant surgeon and who had pre‐operative FNA were enrolled in this retrospective study. The pre‐operative FNA results were compared with definitive histological diagnosis following thyroid resection. Fine needle aspiration cytology was performed using aspirate and non‐aspirate techniques on each thyroid swelling. The cytological sample was assessed by a single cytopathologist and was classified as inadequate, non‐neoplastic, neoplastic, suspicious or indeterminate. The histology was classified as non‐neoplastic (benign) and neoplastic (malignant). Results Fine needle aspiration cytology analysis revealed 94 (13.88%) non‐neoplastic, six (65.27%) neoplastic and 20 (4.16%) suspicious aspirates. Twenty (13.88%) samples were inadequate and four (2.77%) samples were indeterminate. Histological analysis showed 118 (81.94%) benign, 26 (18.05%) malignant specimens. Fine needle aspiration cytology had a sensitivity, specificity and accuracy rate of 52.6%, 86.6% and 79.1%, respectively for diagnosing thyroid malignancy. Conclusion The results are comparable with the current published data and demonstrate that FNA cytology in our hands is accurate investigation for pre‐operative diagnosis for the detection of thyroid malignancy.     

Diagnostic significance of flow cytometric DNA analysis applied for the detection of cancer cells in bronchial washing fluid

Since both DNA aneuploidy and increased proliferative activity are important characteristics of malignant neoplasms, flow cytometric (FCM) analysis was used to examine the cell content in bronchial washing samples obtained via fiberoptic bronchoscopy from 73 patients. The results were compared with the results of histology and conventional cytology. The patients included 30 with bronchial carcinomas, 12 with bronchopneumonia and 31 with no evidence of lung disease. Of the 30 patients with histologically confirmed lung cancers, 25 showed either aneuploid stem lines (19 cases) or high levels of proliferation (6 cases) as determined by analysis of cell-cycle stages. The same rate of cancer cell detection was obtained by cytology. In the 43 cases with neither histologic nor clinical evidence of malignancy, FCM data yielded 5 false-positive results, as compared to 4 erroneous suspicions of cancer by cytology. From these data, it is concluded that FCM measurements of both DNA ploidy and proliferative activity may complement conventional cytology in the recognition of bronchial carcinomas.     

Flow cytometric DNA analysis on fine needle aspiration biopsies of liver lesions

Flow cytometric DNA analysis on fine needle aspiration biopsies of liver lesions The DNA cell content of 39 fine needle aspiration biopsies (FNAs) from five benign liver lesions, nine hepatocellular carcinomas (HCCs), and 25 metastatic tumours was analysed in a prospective fashion by flow cytometry (FCM). All benign lesions were diploid. Aneuploidy was found in five (55.6%) HCCs and in nine (36%) metastatic tumours. DNA index (DI) differences were not significant. The S-phase fraction (SPF) was higher in the malignant tumours, both combined (P < 0.02) and separated primary and metastatic (P < 0.05). We could not demonstrate an association between diploidy and percentage of benign hepatocytes in the smears of malignant tumours. The serum alpha-fetoprotein (AFP) level did not correlate with ploidy, DI, or SPF in the HCCs. In conclusion, ploidy and DI do not discriminate between benign and malignant liver lesions, but the SPF is higher in malignant tumours. DNA analysis does not help to distinguish primary from metastatic liver tumours. The presence of benign hepatocytes in samples from malignant tumours does not seem to influence the analysis of ploidy by FCM.     

Value of repeated fine needle aspiration cytology in patients with nodular goiter

OBJECTIVE: To assess the value of reaspiration cytology in benign nodular thyroid disease. DESIGN: We prospectively studied 400 patients (365 women, 35 men) aged 46 years (18-89) with nodular thyroid disease and initial benign fine needle aspiration cytology (FNAC). Reaspiration of the same nodule was performed in a median follow-up time of 14 months (6-18). RESULTS: Repeat FNAC was benign in 346 patients (86.5%), insufficient for diagnosis in 42 (10.5%), suspicious in 16 (2.5%) and malignant in 2 (0.5%). All diagnostic changes to suspicious malignant cytology took place in patients with solitary nodules. Surgery confirmed thyroid cancer in the 2 patients with malignant cytology, in 5 of 10 patients with suspicious cytology and in none of 39 patients with benign cytology who underwent surgery for other reasons. Clinical changes (size increase or local symptoms) were not related to changes in cytologic diagnosis after a second aspiration, nor with the results of the biopsy. CONCLUSION: Repeat aspiration cytology of thyroid nodules may correct initial false negative results because of cytologic misdiagnosis, occurring in 1.75% of patients, whereas clinical changes did not contribute to diagnosis change. Repeat aspiration cytology is recommended in all patients with nodular goiter.     

Comparison of flow cytometric data obtained using fresh and paraffin-embedded lymphoid tissue

Flow cytometric (FCM) DNA analysis was carried out on 24 lymph nodes: 13 from benign reactive hyperplasias and 11 from non-Hodgkin's lymphomas. FCM was performed on two types of samples: (1) fresh cell suspensions and (2) suspensions prepared from formalin-fixed, paraffin-embedded sections. FCM of fresh samples detected aneuploidy in 23 of the 24 cases while FCM of paraffin-embedded samples detected aneuploidy in only 6 of the 24 cases. Those six cases were lymphomas considered histologically as having a poor prognosis. Only one case, a lymphoma, was euploid with both methods. The coefficients of variance determined in each case for both methods were found to be within "normal ranges," but were greater in the paraffin-embedded specimens. The results suggest that FCM DNA analysis of formalin-fixed, paraffin-embedded sections does not have as great a resolution capacity as does analysis of fresh cell suspensions, since the former failed to detect cell populations that had a small degree of aneuploidy (close to the 2n population).     

Cytologic studies of the fallopian tube in patients undergoing salpingo-oophorectomy

Background

Mounting evidence suggests the fallopian tube as the origin for ovarian high grade serous carcinoma (HGSC). We attempted to identify the tubal cytological features that allow us to distinguish malignant from benign conditions.

Methods

Tubal specimens (n = 56) were collected from patients who underwent bilateral salpingo-oophorectomy (BSO) due to various clinical indications. A standard procedure to collect fallopian tube brushings from freshly received surgical specimens was developed. Cytological diagnoses were classified into three categories: benign, atypical, and suspicious for malignancy/malignant. Cytological variables of individual cells and epithelia were subjected to statistical analysis. The fallopian tube histology was used as diagnostic reference for confirmation of cytology diagnosis.

Results

Among the 56 fallopian tube specimens, 2 (3.7 %) showed inadequate cellularity preventing further evaluation, 11 (20.4 %) were diagnosed as malignant or suspicious of malignancy, 7 were atypical, and 36 were benign. The presence of three dimensional clusters (p < 0.0001, Fisher’s Exact Test), or prominent nucleoli (p = 0.0252, Fisher Exact test) was highly correlated with the diagnosis of malignancy. The suspicious malignant/malignant cytological diagnosis was also highly correlated with presence of HGSC with or without serous tubal intraepithelial carcinoma (STIC).

Conclusions

Tubal cytology may be useful for ovarian cancer screening and early detection.

     

Diagnosis of bladder cancer with urinary cytology, immunocytology and DNA-image-cytometry.

DNA-image-cytometry and antibodies directed against the Lewis X- and the 486p 3/12 antigen were applied to improve diagnostic accuracy of urinary cytology for the detection of bladder cancer. Cytology, immunocytology and DNA-image-cytometry were performed in spontaneously voided urine samples and barbotage bladder washings from 71 patients. The DNA content was determined using the CM-1 Cytometer according to the recommendation of the ESCAP Consensus Report on Standardization of DNA-image-cytometry (1995). For immunocytological examination we used the monoclonal anti Lewis X antibody P-12 and antibody 486p 3/12. All patients underwent subsequent cystoscopy and for any suspicious lesion biopsy or transurethral resection was done. Histological findings revealed 31 patients with transitional cell carcinomas of different stages and grades of malignancy. 40 patients had various benign diseases of the urinary bladder. Cytology yielded a sensitivity of 68% and a specificity of 100%. DNA aneuploidy was detected in 81% of cancer patients with a specificity of 100%. By combination of these two methods the overall sensitivity increased to 87%. Immunocytology with Lewis X and 486p 3/12 antibodies showed reactivity in 84% and 87% in combination with a specificity of 80% and 70%, respectively. By combining urinary cytology, immunocytology and/or DNA-image-cytometry the overall sensitivity increased to 94% with no change in specificity. DNA-image-cytometry should be used to evaluate particularly urothelial cells suspicious for malignancy in urinary specimens. Because of low specificity the monoclonal antibodies against Lewis X- and 486p 3/12 antigens are not helpful in screening for bladder cancer. Nevertheless, their high sensitivity may justify their use in case DNA image cytometry is not available and in the follow up of patients with transitional cell carcinoma.     

Proffered papers 14.00–15.00 Tuesday 16 September 2003

Background  ERCP-directed brush cytology is used to sample lesions of the pancreatic and biliary ducts and the ampulla of Vater. With conventional preparations, the sensitivity and specificity range from 44% to 63% and 80% to 98%, respectively, and increased N : C ratio, nuclear molding and loss of honeycombing are reliable features of malignancy. The performance and morphology of specimens prepared by ThinPrep, a liquid-based cytology technique is mostly unknown.
Methods  The laboratory information system was searched for all cases prepared by ThinPrep. Patient disease classification of benign or malignant was determined by linkage with the provincial cancer registry and was the gold standard against which sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated. True positives and negatives were reviewed to identify predictive cytomorphologic features.
Results  Between 1996 and 2001, there were 149 ThinPrep specimens; 55 (37%) were reported as positive for malignancy and 94 (63%) as negative. Disease was classified as malignant in 86 (58%) patients and benign in 63 (42%). There were 42 false negative, 11 false positive, 52 true negative, and 44 true positive cytology results. Sensitivity was 51.2% (CI; 40.2 : 62.0), specificity 82.5% (CI; 70.5 : 90.6), and PPV and NPV 80.0% (CI; 66.6 : 89) and 55.3% (CI; 44.7 : 65.5), respectively. Cell groups with crowded, enlarged, irregular nuclei and nuclear features of vesicular chromatin and large, multiple irregular nucleoli correlated with malignant disease, while monolayered sheets of uniform columnar cells, regular nuclei and a finely granular chromatin correlated with benign disease.
Conclusions  The performance of ThinPrep brushings from this anatomic site equals conventional preparations. Cytomorphologic features of malignancy are more frequent and pronounced with ThinPrep.